The present invention relates to a rotation device of a buckle for use in an automobile seat belt; and, more particularly, to a rotation device of a buckle for used in an automobile or a vehicle having a reduced noise level during a rotation of a main body of the buckle and constructed to be easily assembled.
In general, an automobile or a vehicle is provided with a seat belt device for limiting the forwarding movement of the vehicle occupant, in an emergency situation, e.g., a collision or a crash, wherein a belt webbing whose one end is wound around a retractor mounted inside lower portion of pillar is introduced into the driver""s compartment through an internal space of the pillar and a tongue provided in the other end through an anchor mounted on the pillar is insertable into a buckle fixed on a seat frame.
The buckle is rotatable in a predetermined angle through a rotation device. In FIG. 1, a conventional buckle is shown. As shown, the buckle is provided with a buckle main body 2 locking or releasing a tongue plate provided in a belt webbing (not shown), a stalk 3 rotatably connected to a rear portion of the main body 2 at its one end and fixed to a seat frame at the other end.
The main body 2 is made of resin and is provided with an insert hole (not shown) into which the tongue plate is insertable and has a push button (not shown) for releasing the tongue plate engaged into the insert hole.
The main body 2 constructed in this manner is connected to one end of the stalk 3 to be rotatable by a rotation device 4 mounted in a rear inner portion of the main body 2.
In other words, the rotation device 4 includes a bottom plate 5a made of a steel plate and seated on an inner bottom surface of the main body 2, a pair of side plates 5b formed by an upward bending process from the bottom plate 5a and having a pair of lugs 5b-l bent inwardly, respectively, a buckle base 5 provided with a circular plate portion integrally formed with one end of the bottom plate 5a and having a through hole 5d formed therethrough, a collar 6 having a cylindrical shape 6b, a flange 6a integrally formed with one end of the cylindrical shape 6b, which is seated on the circular plate portion 5c of the buckle base 5 to support the buckle base 5, allowing the buckle base 5 to pivot with respect to the stalk 3 in a width direction of the seat, a pair of guide portions 6c formed at both ends of the flange 6a, the guiding portion 6c surrounding a peripheral surface of the circular plate portion 5c and a protrusion portion 6d protruding from a portion from a center to a bottom of the cylindrical shape 6b to be eccentric, a stalk 3 having an insertion hole 3d into which the cylindrical shape 6b of the collar 6 is inserted, an elastic spring 7 positioned on an upper surface of the stalk 3 to allow the cylindrical shape 6b of the collar 6 to be inserted into the insertion hole 3a, a rivet 8 inserted into through hole 5d of the circular plate portion 5c of the buckle base 5, the collar 6, the stalk 3, and the elastic spring 7, and a fixing cap 9 having a hole 9a for receiving an upper portion of the rivet 8 to fix the components therebetween and a lug 9b engagable with the lug 5b-l formed with the side plates 5b of the buckle base 5.
On the other hand, there are shown another prior art buckle in FIGS. 3 and 4 which has a same function as that of the buckle shown in FIGS. 1 and 2. As shown, the buckle 10 is provided with a main body 11 for locking or releasing a tongue plate provided in a belt webbing, and a stalk 12 being rotatable at its one end, while the other end is fixed to a seat frame.
The main body 11 is made of resin and is provided with an insert hole (not shown) into which the tongue plate is insertable and a push button (11a) for releasing the tongue plate engaged into the insert hole.
The main body 11 constructed in this manner is connected to one end of the stalk 12 to be rotatable by a rotation device 13 mounted in a rear inner portion of the main body 11.
That is, the rotation device 13 includes a bottom plate 14a made of a steel plate and seated on an inner bottom surface of the main body 11, a pair of side plates 14b formed by an upward bending process from the bottom plate 14a and having a pair of cutouts 14b-l into which one end of the fixing cap 18 is engaged, a buckle base 14 provided with a circular plate portion 14d integrally formed with one end of the bottom plate 14a and having a through hole 14c formed therethrough and a pair of lugs 14e for an engagement with a collar 15 to be described later protruding from both ends of the circular plate portion 14d, a collar 15 having a cylindrical shape 15b, a flange 15a formed at one end of the cylindrical shape 15b, the flange 15a being seated on the circular plate portion 14d of the buckle base 14 to support the buckle base 14, allowing the buckle base 14 to pivot with respect to the stalk 12 in a width direction of the seat and a pair of recesses 15c for receiving the lugs 14e formed on the circular plate portion 14d of the buckle base 14, a stalk 12 having an insertion hole 12a into which the cylindrical shape 15b of the collar 15 is inserted and a pair of protrusions 12b outwardly extending from a peripheral surface, an elastic spring 16 positioned on an upper surface of the stalk 12 to allow the cylindrical shape 15b to be inserted into the insertion hole 12a, one end of the elastic spring 16 being engaged with the protrusion 12b, and the other end being fixed with respect to the fixing cap 18 described later, a rivet 17 inserted into through hole 14c of the circular plate portion 14d of the buckle base 14, the collar 15, the stalk 12, and the elastic spring 16, and a fixing cap 18 having a hole 18a for receiving an upper portion of the rivet 17 to fix the components therebetween, a pair of concave portions 18b formed around the fixing cap 18 to receive the other end of the elastic spring 16, and a lug 9b engagable into the cutouts 14b-l formed through the side plates 14b of the buckle base 14.
By the rotation device 4,13 mounted in the buckle 1,10 shown in FIGS. 1 through 4, the main body 2,11 of the buckle 1,10 is rotatable with respect to the seat and returned to an initial state.
That is, by the elastic spring 7,16 provided in the rotation device 4,13 of the buckle 1,10, the main body 2,11 is elastically rotated toward the vehicle occupant. At the moment, the operation of the elastic spring 7,16 and the returning action resulted therefrom are performed through the collar 6,15. The collar 6,15 not only causes an increase of the manufacturing cost and the manufacturing time but also results in noise when it comes into contact with the elastic spring.
It is, therefore, a primary object of the invention to provide a rotation device of a buckle for use in an automobile having an elastic spring without necessitating a collar or any equivalent therefor for its operation, thereby reducing the manufacturing cost, the manufacturing time and the occurrence of the noise.
In order to achieve the object, the present invention provides a rotation device of a buckle for use in an automobile seat belt is provided with a base having a plate-like shape to be mounted on a bottom surface of a main body and provided with a circular plate portion at its one end, the circular plate portion provided with a through hole formed therethrough, and a pair of side walls bent upwardly each of which has a lug bent inwardly to be integrally formed with the circular plate portion as well as the pair of side walls, a stalk whose one end is rotatably mounted on an upper surface of the circular plate portion of the base and has a hole formed therethrough and a stopper portion formed around the end of the stalk and provided with a protrusion for being contacted with an inner surface of the side wall of the base and an abutment for limiting a rotation angle of the main body, the stalk having a protrusion for stopping a rotational movement, an elastic member whose one end is contacted to the protrusion for stopping a rotational movement and having an elasticity and a through hole formed therethrough, so that the elastic member provide a restoring force when the main body is rotated, a rivet inserted into through hole of the circular plate portion of the base, the holes of the stalk and the elastic spring, and a fixing cap having a hole 135a for receiving an upper portion of the rivet to fix the components therebetween, a lug formed at one side thereof to be engaged with the lug formed with the side walls of the base.
In the rotation device, the elastic member is provided with a lower portion mounted on an upper surface of the stalk, an upper portion contacted with a bottom surface of the fixing cap, the lower portion having an arcuate shape containing the through hole and a protrusion receiver for receiving the protrusion for stopping the rotational movement, and the upper portion having a circular cross section, and a plurality of torsional holes formed through the elastic member.
In the rotation device, the stopper portion of the stalk is applied with plastic material.
In the rotation device, the fixing cap is provided with an insertion protrusion inserted into the torsional hole of the elastic member to allow the elastic member to be assembled at its twisted state when the fixing cap is assembled.
In the rotation device, the elastic member is made of one or compound of the group including the urethane, the rubber and the silicon.
In the rotation device, the elastic member is of a coil spring whose one end is contacted with the protrusion for stopping the rotational movement formed at the stopper portion of the stalk, while the other being kept on a peripheral surface of the fixing cap.
In the rotation device, an inner diameter of a hole formed through the lower portion of the elastic member is larger than that of the through hole of the upper portion.